Canopy switch



Feb. 26, 1929.

P. E. BURNS CANOPY SWITCH Filed larch 1927 Patented Feb. 26, 1929.

UNITED STATES PATENT OFFICE.

PETER E. BURNS, OF SYRACUSE, NEW YORK, ASSIGNOR TO PASS & SEYMOUR, INC.,

015 SYRACUSE, 'N EW YORK, A CORPORATION OF NEW YORK.

CANOPY SWITCH.

Application filed March 9, 1927. SerialNo. 174,021.

This invention relates to electric switches and more particularly to the operating member for such switches.

It is a general object of the present invention to provide a novel and improved form of electric switch.

More particularl it is an object of the invention to provic e, in an electric switch, a novel operating means for the movabl contact engaging member.

Specifically the invention resides in the provision of a rotatable switch stem in the form of a metal rod adapted to have a knob attached to one end thereof, the opposite end of the rod being flattened to provide two parallel faces, there being a strip of insulating material attached to each of the faces so that the two strips may straddle a movable contact engaging member to rotate the same.

Other and further objects of the invention will be more apparent to those skilled in the art upon a consideration of the accompanying drawing and following specification wherein is disclosed a single exemplary embodiment of the invention with the understanding that such changes may be made therein, as fall within the scope of the appended claims, without departing from the spirit of the invention.

In said drawing: I

Figure 1 is a central vertical section of a switch constructed according to the-present invention Figure 2 is a side elevation of the ing member; and

.Figure 3 is a transverse section on line of Figure 1. In the usual construction of what are technically known as canopy switches, an insulating body is provided having a recess. Two contacts are arranged diametrically opposite on the walls of the recess and a more or less Z-shaped spring member is adapted to be rotated in the recess to have its ends engaged with these contacts to bridge the same. For the purpose of rotating the spring member it has been customary to provide a rod of insulating material such as fiber, having a slit in its end to receive the center portion of the Z-shaped spring. The outer end of this fiber rod was attached by suitable means to a threaded metal rod which rotated in a suitable bearing member and carried on its outer'end an operatoperatsame time effects a great reduction in the number of operations and hence in the cost of producing the part.

Referring to the drawing, there is disclosed at 10 a suitably molded insulating body of any desired shape in plan, such as that shown in Figure 3, having the recess 11 therein receiving on-its side Walls which are suitably notched as at 11, two contacts but one of which, '12, is visible in Figure'1.

These contacts are diametrically opposed and are adapted to be engaged to complete the circuit between the two by means of a substantially Z-shaped rotatable member 13 which is formed of spring metal such as bronze into the form shown in Figure 3 and having the central portion 14 and the wings or arms 15. In one position the wings engage the contacts 12 to bridge the same and in a position 90 therefrom the wings engage the walls of the recess 11' and the circuit between the contacts 12 is open.

lead from the contacts 12 to conductor wires extending from the insulating body. At 16 a portion of one of the extensions between the contact and the terminal wire is seen in section. A washer 17 is positioned on the top edges of the spring member and a suitable thin sheetof insulating material 18' covers the whole face of the insulating body 10 and closes the recess with the exception v of the small circular opening 19 in the insulating member 18. A metal cover 20 is placed overthe insulating member 18 and is secured in position by suitable fastening means. For purposes of illustration there are shown screws such as 21 passing'thru the insulating body and received in threaded openings in the cover. This cover carries a metal bushing 22, the reduced end of which is spun over the edges of a hole in the pro- Suitable terminal members (not sho\vn)- thruout the majority of its length and having. its one end flattened by a suitable stamping or swaging operation shown best at29 in Figure 1. Figure 2 shows how the width of therod is increased by this flattening operation. The threaded portion of the rod is, adapted for rotation in the bore of the bushing. In order to connect the rod to the central portion 14 of the spring 13 it has applied to each race of the flattened portion one of the insulating strips 30. fThese strips are small rectangles of thin insulating material such as fiber, bakelite or the like. The thickness or the .portion 29 is just slightly greater than that of the spring 'll so that when the two strips 30'are secured to the faces oi the flattened portion 29 by the hollow rivet 31 or other suitable fastening means they are spaced 'apart a suilicient distance to readily straddle the central portion 14 of the spring. The

length of the strips 30 is such that when the outer ends are substantially against the bottom of the recess in the insulating body the inner ends bear against the shoulder 32 at the unction of the two bores in the bushing and serve to prevent withdrawal or the peratingme'mber. A suitable knob 33 is nternally threaded as shown in Figure l to be IGCBLVGCl on the threaded portion of the stem 28. The switch spring can be rotated in but one direction owing to the ratchet like formation in the walls of the recess in the insulatbody and that direction is clockwise, and the thread is therefore right hand on t'llG'StQlIl. Anyattemptto-reverse the (llICQC- tionofoperation of the switch only serves to unscrew the nut and no damage can thereiore'bedone to the movable spring member. The construction of the switch operator 1S extremely simple as can be seen troin'Figure 2 where it comprises'only the rod 28, usu:

ally a threaded brass rod which requires a single 'operation to flatten and punch to receive the rivet. A single punch press operation fori'iisthe strip 30 withthe rivet'hole thereinand a single assembly operation oins the three parts together. The cost of mania facture is therefore extremely low.

Having thus described the invention, what is claimed as new-and desired to be secured "by Letters-Patent is 'lxI'n an electric switchin combination,

- signature.

stationary contacts, a movable conductor adapted to bridge said contacts, a rotatable operating stem for said switch formed oi metal, a flattened 'end on said stem, 'a pair oi insulating strips,'on'e"secured to each fiat face, said strips straddling said movable conductor to operate the same.

2. In an electric switch in combination, an 7 iiisiilatin'gbody, stationary contacts thereon,

a movable contact member adapted for retation into and out of contact with said stationary contacts, an operating stein rotatable about its axis, a pair OflIlSLllZttlilQ strips one engaging eaclrside of said movsecured to said body,a metal rod rotatable V in said cover and having an operating knob on the outer end-thereof, a flattened inner endon said rod, apair of insulating. strips, one secured to each race or said flattened portion, said strips straddling the center 01' said Z-shaped spring for the purpose described. 1

4. An operating means for an electric switch, including in combination, a metal rodhaving a flattened end providing two substantially parallel oppositely disposed iacesand an insulating strip secured-toeach face, said strips being spaced apart by'the thickness of said flattened end cf'said rod.

5. An operating means for an electric switch, including in combination, a metal rod having a flattened endproviding' two substantially parallel outer faces, a pair of insulating strips each having one end overlapping said flattened rod end races and a fastening means passing thru said strips and flattened end .to secure themrall together.

6. An operating means for a switch oi? the canopy type including in combination, a metal rod threaded atone end'to receive a knob, the other end of said rod being fiat tened, a pair ofsubstantially rectangular strips of insulating material fastened one eithe face of sai'dfiattened portion, said strips extending beyond the end of saidflat- JGllQCl portion for the purpose "described.

'7. 7 An operator for the movable element of a canopy switch comprising a pair of in sulating arins,portions of which are adapted to straddle said element and a metal rodbe tween and secured to other portions of said arms. V ln testimony'whereofl hereunto allix my PETER? E; BURNS. 

